Device for cleaning internal threads of pipes



1956 J. B. BAGGETT 2,764,991

DEVICE FOR CLEANING INTERNAL THREADS OF PIPES Filed may 18, 1955 IO I JOE BARRON BAGGETT BY \ltw. s M

ATTO NEY IN VEN TOR. v

DEVICE FOR CLEANING INTERNAL THREADS F PIPES Joe Barron Baggett, Lafayette, La., assignor to Sun Oil gompany, Philadelphia, Pa., a corporation of New ersey Application May 18, 1955, Serial No. 509,280

4 Claims. (Cl. 134-167) The present invention is directed generally to a pipe cleaning device. Specifically, the apparatus is directed to a device for cleaning drilling mud from the internally threaded end of borehole drilling pipe.

The use of rotary drilling equipment common in oil well drilling requires the insertion and removal of sections of drill pipe from which the rotary drill bit is suspended, during the drilling procedure. As the drill progresses, the bit is cooled and the particles of earth are removed from around the bit by the circulation of drilling mud downwardly through the drill pipe to return upwardly through the annulus of the borehole. The fluid presently used for this purpose is a thixotropic liquid tending to gel when not circulated and is highly viscous. Although it gels readily, it is easily returned to its proper workable state by proper agitation.

Drill pipe used to suspend the rotary bit is removed and replaced to serve the various drilling operations. For example, to sharpen a bit it is necessary to remove the bit from the borehole, disengaging the drill pipe into sections as the bit is withdrawn from .the hole. The sections are engaged by threaded connections, each length having a male threaded portion called the pin end and an internally threaded portion called the box end. Each section is disconnected and lifted by the proper derrick tool to stand within the derrick structure ready for later use. The drilling mud gels and stays in the pipe sections either completely filling the drilling pipe, or leaves a heavy coating on the internal wall.

On resuming the drilling operation, the sections of the drilling pipe internally coated or filled with drilling mud are lifted and aligned for attachment to each other by inserting the pin end into the box end and securing them together. The pin end is readily washed free of drilling mud by the use of a water stream. The box end requires a longer, more tedious, cleaning operation. However, both ends must be cleaned and lubricated before they are threaded, or spun together. It is the primary object of this invention to provide a device for readily cleaning the internal thread of borehole drilling pipe, permitting easy and ready coupling of drilling pipe sections.

The invention will be further illustrated by reference to the drawing, in which:

Figure l is a diagrammatic elevational view of the cleaning device in operation.

Figure 2 is an elevational view, partly in section, of the device at the beginning of a cleaning operation.

Figure 3 is a sectional view of Figure 2 taken on line 33.

Figure 4 is a sectional view of Figure 3 taken on line 4-4.

A general description of the device emphasizes the simplicity of the mechanism. Briefly, a directioned spray of Water is coupled with a concentrically positioned plug for disturbing the jelled drilling mud, all enclosed in a shield adapted to operatively enclose the box end of the pipe.

tates Patent ice A liquid source is connected to the spray element and controlled with a conveniently located valve by the operator. An easily handled and etliciently operating device is obtained by combining the plug and spray, and also by directioning the spray openings to cooperate with the cleaning action of the plug as it moves into the end of the pipe.

Referring now to the drawing, Figure -1 is a diagrammatic view of a suggested arrangement of the operating elements of this invention shown in use under the circumstances for which it was'designed. An oil well derrick 10 is shown in operating position relative to a section of drilling pipe 12 standing in operating position in the ground. The cleaning device of this invention, inclusively numbered 14, is shown in the final cleaning position relative to the positioned drilling pipe 12. A source of water for cleaning purposes to be used with the drill pipe cleaning mechanism 14 is shown as a water tank 16, mounted on a conventional tower 18. A flexible hose 20 connects the cleaning device to the Water tank 16. It will be understood that the source of cleaning water here is symbolic only and may take any form available.

The internal pipe thread cleaning device 14 is shown as one element in Figure 2 immediately above the second element, the drill pipe 12. The cleaning device includes a shield 22 shaped as an inverted cup which extends downwardly and encloses a concentrically positioned plug 24. This plug extends substantially the full depth of the shield, but may be terminated at the most convenient point, as will later be understood in discussing the operation of the device. The plug 24 is divided into an upper portion 26, which presents a shoulder 28 about midway of the length of the plug and a plurality of downwardly and radially directed spray openings 30 flaring outwardly from a central passageway 32. The lower portion of the plug 34 below the shoulder 28 is of uniform diameter, rounded on the bottom, and of a size that will fit into the box end 36 of pipe 12 with some clearance to allow for the escape of mud, and extend below the lowest thread of that pipe section. An enlarged elevational view of the operating section of plug 24 is shown partially in section in Figure 3 and a cross-section through the downwardly flaring radially extending spray openings is shown in Figure 4.

A rigid tubular connector 38 extends from the flexible pipe 20 and connects to the central passageway in the upper part of plug 24 through shield 22. The assembly is held in fixed relation by conventional threaded portion 41 of the tube 38 and washer 40 and nut 42. A quick acting valve 44 is inserted in the rigid tube 38 between the water source 16 and the spray openings in the plug 24, and is conveniently placed for easy operation. A spring handle 46 is positioned for easy operation of the valve by the operator.

Those versed in the art will readily understand the operation of the above-described device from the description of the elements. However, to emphasize the simplicity of the mechanism and the ease with which the drilling mud deposit is removed from the box end of the drill pipe, a typical operation in which this device would be used will be described.

It appears to be normal procedure to remove the drill pipe as it is brought up from the well borehole and stand it against the stabbing board in the derrick 10, and not clean the threaded ends or box ends of the drill pipe until it is lowered into place for re-use. It will be understood, however, that the procedure could be reversed and the cleaning steps accomplished either on removal of the drill pipe from the drill hole or on re-use of the drill pipe as is now to be described.

Starting with the step of picking up a length of drill pipe preparatory to spinning it into engagement with an upwardly extending box end and preparatory to rotating downwardly into the borehole, a stream of water is played on the pin end of the drill pipe. The-clinging dirt and mud is removed, the thread lubricated and the drill pipe is spun into connection with the section below. The drilling assembly is now lowered until the box end of the connected length of drill pipe is within reach for ease of cleaning.

The cleaning device 14 is held in position over the box end of drill pipe -12 as shown in Figure 2 and gradually lowered until plug 24 comes into contact with the drilling mudin the box end. By forcing the plug 24into the mud, the highly viscous fluid is forced'to spill over the end of pipe 12 around the freely fitting plug 24, and admit the plug as it works its way downward. The operator releases quantities of Water into the disturbed mud through the'spray openings to assist this overflow. The stream of water isprevented from dispersing beyond the limits of the pipe by the shape and size of shield 22 and the direction of the spray openings in the body of the'plug. By repeated use of the water and downward movement of the plug, the mechanism is forced into complete engagement with the end of the pipe where repeated spurts of water, directioned against the internal threads by the spray openings, clean the residue of the mud from the pipe threads 36. The cleaning device is thenremoved from the box end of the pipe, lubrication placed upon the pin end of the next section of drill pipe, and the string is spun together. Thisaction is repeated for each length of drill pipe.

What is claimed is:

1. A device for cleaning internal thread of borehole drilling pipe comprising a shield shaped to receive and enclose the end of the pipe, a plug concentrically positioned in said shield, said plug having a number of radially extending spray openings from a common central passageway to the plug surface in such. position to direct a liquid spray within the confines of the shield, a conduit connected to said central plug aperture through said shield for transmitting liquid under pressure to the radial spray openings of the plug, and valve means in said conduit controlling the flow of liquid therethrough.

2. A device for cleaning internal threads of borehole drilling pipe comprising a cup flared outwardly at the open end to receive the end of the drilling pipe, a plug attached concentrically at the upper end in said cup extending substantially the full depth of the cup and having a plurality of downwardly directed, radially spaced spray openings connecting a central passageway with the periphery of said plug above the lower end, a conduit connectinga liquid supply source to said central aperture for distribution through the radially spaced spray openings with appreciable force, anda liquid control valve in said conduit.

3. A device for cleaning internal threads of borehole drilling pipe comprising an inverted cup-shaped shield flared-to receive the end ofthe pipe to be cleaned, a concentric plug positioned in theinverted cup-shaped shield and extending substantially the full depth of said shield, said plug being divided into equal upper and lower portions bya shoulder offset reducing the size of the lower portionfrom the upper portion, .said plughaving a plurality of radially distributed spray openings breaching the periphery of the plug at the shoulder separating the .two portions and extending inwardly and upwardly in such position to direct a liquid spray within the confines of the inverted cup, a conduit connecting the shield and plug together for transmitting pressured wash liquid to the radially disposed spray openings of the plug, and liquid 'flow control means in said conduit.

4. A device forcleaning internal threads of borehole drilling pipe comprising a shield shaped to receive and enclose the end of the pipe, a cylindrically shaped plug within and extending concentrically of the shield having an imperforate pipe-entering end adapted to slidably fit into the pipe to be cleaned, the upper end of the plug having a passage'for reception of wash liquid, the plug having a plurality-of spray openings extending obliquely downwardfrom said passage and breaching the plug wall above its lower-'pipe-entering end, and a valved conduit communicating with said passage for connection with a source of washiliquid.

References Cited in the file of this patent UNITED STATES PATENTS 1,552,998 Menge Sept. 8, 1925 

